Ajedrecista wrote:Then, I opened the merged file made with Merge_PGN.bat with Notepad and searched one by one, until I found a checkmate in 1090 half-moves:
[d]8/6R1/8/6N1/3k1K2/1B6/7n/7q w - -
I was thinking this can't be right, since the longest win in this tablebase is well-known to be 517 (full) moves (see e.g. here, item 316). However, that is 517 moves to conversion. Maximal distance to mate is apparently again quite a few moves more (and achieved by a somewhat different position).
I don't think that "1090 half-moves" contradicts to "517 moves to conversion plus quite a few moves more until mate" (1090 / 2 = 545; 545 - 517 = 28)
Ajedrecista wrote:Then, I opened the merged file made with Merge_PGN.bat with Notepad and searched one by one, until I found a checkmate in 1090 half-moves:
[d]8/6R1/8/6N1/3k1K2/1B6/7n/7q w - -
I was thinking this can't be right, since the longest win in this tablebase is well-known to be 517 (full) moves (see e.g. here, item 316). However, that is 517 moves to conversion. Maximal distance to mate is apparently again quite a few moves more (and achieved by a somewhat different position).
I don't think that "1090 half-moves" contradicts to "517 moves to conversion plus quite a few moves more until mate" (1090 / 2 = 545; 545 - 517 = 28)
syzygy wrote:Letting the number of moves depend on available egtb knowledge seems silly to me.
Not to me. It means that your rule is not artificially interfering with the game.
If a contrived rule is needed to ensure the game ends, IMO it should be as permissive as possible, so that the other rules take priority over it.
But how would this work? Do you give more rights to engines that claim to have certain tablebases? And what about engines that let their pieces wander around aimlessly, but manage to keep a theoretically won position? They have a win, so they should be given the opportunity to find it? Or should positions known to be won just be adjudicated as a win, whether the engine has the tablebase or not?
syzygy wrote:Letting the number of moves depend on available egtb knowledge seems silly to me.
Not to me. It means that your rule is not artificially interfering with the game.
If a contrived rule is needed to ensure the game ends, IMO it should be as permissive as possible, so that the other rules take priority over it.
But how would this work? Do you give more rights to engines that claim to have certain tablebases? And what about engines that let their pieces wander around aimlessly, but manage to keep a theoretically won position? They have a win, so they should be given the opportunity to find it? Or should positions known to be won just be adjudicated as a win, whether the engine has the tablebase or not?
I think there should be some limit, but not a 50 move limit. Whether it's a bigger move limit or addressing it with a time limit, I'm not sure (and I'm not going to think too much about it just to write a forum post ).
I agree with a statement previously in the thread, that this should be a tournament issue and not a game issue. Different tournaments could decide to address it with move limits, adjucation or whatever.
).